Complexification of Lambda Length as Parameter for SL(2, C)

A coordinate-system called λ-lengths is constructed for an SL(2, C) representation space of punctured surface groups. These λ-lengths can be considered as complexification of R. C. Penner's λ-lengths for decorated Teichmuller spaces of punctured surfaces. Via the coordinates the mapping class group acts on the representation space as a group of rational transformations. This fact is applied to find hyperbolic 3-manifolds which fibre over the circle.